Re: carbs, fibre and US Agriculture database

[Guest guest]

You are right about subtracting the fiber from the carbohydrates, but

you should not subtract this value from the calories listed in the

USDA database because the fiber has already been subtracted.

You can check this by computing the total calories from the

components:

The energy is listed as 34 kcal, and the material content is 2.82 g

protein, 0.37 g fat, 6.64 g carbohydrate and 2.6 g fiber.

2.82 * 4 = 11.28 kcal

0.37 * 9 = 3.33 kcal

(6.64 - 2.6) * 4 = 16.16

And the energy computed from the components is

11.28 + 3.33 + 16.16 = 30.77

Our computed energy is 3.23 kcal lower than the listed value due to

rounding, etc. The calories per gram of protein, carbohydrate and fat

are not exactly 4, 4 and 9.

If the USDA database had not subtracted the fiber, the energy value

listed would have been closer to 41.17 kcal. Subtracting the fiber

you would then get 41.17 - (2.6 * 4) = 30.77

Tony

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From: " rwalkerad1970 " <rwalkerad1970@y...>

Date: Thu Dec 23, 2004 1:22 pm

Subject: carbs, fibre and US Agriculture database

Hi all, I read recently that the American Nutrition Figures usually

count fibre as a carbohydrate calorie, can any one tell me if my

reasoning is therefore correct and if this is true.

If I choose raw broccoli from:

http://www.nal.usda.gov/fnic/foodcomp/search

For 100g the data listed is - 34 calories, 6.64g carbs and 2.6g

fiber. Now am I correct to minus the fibre calories from the carb

calories thus leaving the actual carb figure as 4.04g (6.64g minus

2.6g) and am I right in then taking those 2.6g carbs from the total

calories resulting in 2.6x4 (4 being calories for a gram of carb)

and therefore resulting in a total calories of 23.6. Is this

correct ?

thanks in advance, richard ..

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